Russia's US election hacking far wider than first thought

Russia's attempts to hack the United States 2016 presidential election were more extensive than previously thought, a new report reveals.

The cyberattack included breaches of voter databases and software systems in twice as many states as earlier reported, US news website Bloomberg says.

Russian US election hacking: What you need to know

On June 6, a National Security Agency document was leaked to news website The Intercept, detailing attempts by Russia's GRU intelligence agency to hack the computers of voting officials across the US, Vox explains.

The attacks were aimed at voter registration systems, not voting machines themselves. There's no evidence the Russian government changed Americans' votes, but it's believed they could have affected voting by deleting people's registration details, causing delays on polling day.

Soon after the story broke, a US intelligence contractor named Reality Winner was charged with leaking a classified document.

Investigators in Illinois have found evidence hackers tried to delete or change voter data, Bloomberg reports.

The breaches are now thought to have hit systems in 39 states, and included accessing a campaign finance database in at least one state.

The extent of the hacks was so concerning to then-President Barack Obama's administration that they took the step of complaining directly to the Russian government at the time.